Furnace wall construction



8 Sheets-Sheet l ug 15, l933- J. s, BENNETT FURNACE WALL CONSTRUCTION Filed March 22, 19.28

All@ l5, 1933 J. s. BENNETT FURNACE WALL CONSTRUCTION Filed March 22, 1928 8 Sheets-Sheet 2 'Gamma/y ug- 15, 1933- J. s. BENNETT FURNACE WALL CONSTRUCTION Filed March 22, 1928 8 Sheets-Sheet 3 rlllrllalilill.

Aug'. 15, 1933. J. s. BENNETT 1,922,521

FURNACE WALL CONSTRUCTION Filed March 22, 1928 8 Sheets-Sheet 4 Aug. 15, 1933o J. s. BENNETT l,922,52l

FURNACE WALL CONSTRUCTION Filed March 22, 1928 8 Sheets-Sheet 5 ZUZ Zag

8 Sheets-Sheet 6 J. S. BENNETT FURNACE WALL CONSTRUCTION Filed March 22,

Aug, l5, N333.,

Aug. 15, 1933. .1.5. BENNETT FURNACE WALL CONSTRUCTION Filed March 22, 1928 8 Sheets-Sheet '7 Aug. 15, 1933. J. s. BENNETT FURNACE WALL CONSTRUCTION Filed March 22, 1928 8 Sheets-Sheet 8 Patented Aug. 15, 1933 FURNACE WALL CONSTRUCTION Joseph S. Bennett, Philadelphia, Pa., assignor to American Engineering Company, Philadelphia, Pa., a Corporation of Pennsylvania Application March 22, 1928. Serial No. 263,765

4 Claims.

My invention relates to wall constructions, such, for example, as are applicable to furnace installations.

One object of my invention is to provide a 5 furnace end wall construction embodying fluidcooling means, whereby the temperature of the wall may be maintained at a predetermined safe value, the construction contemplating in particular a pair of headers, a plurality of cooling pipes extending therebetween, a plurality of re fractory blocks, and means for clamping the blocks in position on the pipes.

Another object of my` invention is to provide a fluid-cooled protective panel for a furnace end wall, particularly applicable to a furnace having protective side-wall constructions of the character set forth in my co-pending application, Serial No. 219,706, led Sept. 15, 1927 and assigned to the American Engineering Company,

as well as the co-pending application of Edward Wheeler, Serial No. 250,237, filed and also assigned to the American Engineering Company.

A further object of my invention is to provide a Suspended protective wall structure, in

combination with means for maintaining the wall in position when expansion occurs.

A still further object of my invention is to provide a furnace comprising a stoker, a protective Structure constituting at least one portion of a wall of the furnace, and means for affording the protective structure a suspended mounting independently of the Stoker.

A still further object of my invention is to provide in a furnace, a stoker structure, a sectional furnace wall, wherein one section comprises a fluid-cooled construction supported by the Stoker structure, and means for supporting another section of the wall independently of the Stoker structure.

A Still further object of my invention is` to provide a fluid-cooled protective structure Vfor a wall comprising a header, and means for affording the header a cushion support.

A still further object of my invention is to provide a sectional wall, of which one Section comprises a fiuidmooled protective structure mounted on a Stoker, a second section comprises a brick or tile structure mounted independently of the Stoker, and a third section includes an expansion joint and is mounted immediately adjacent to the brickwork section.

Other objects and applications of `my invention., as well as details of construction and operation, whereby my invention may be practiced,

will be apparent more fully hereinafter, when taken in connection with the accompanying drawings, wherein Fig. 1 is a longitudinal sectional view of a furnace embodying my invention;

Fig. 2 is an enlarged detail, horizontal sec- 60 vtional view of the front end wall, the sectional plane being taken on the line 2 2 of Fig. 1;

Fig. 3 is a further enlarged detail, horizontal sectional View, showing the tie bolts associated with a lower edge portion of the fluid-cooled protective structure;

Fig. 4 is a vertical sectional view taken on the line 4 4 of Fig. 3;

Fig. 5 is a similar view taken on the line 5 5 of Fig. 3, illustrating further the position of the hook bolt for securing in position the clamping means for the ram-box caps;

Fig. 6 is an. enlarged end elevational view of one of the supporting boxes for the upper header and the supporting cross beams therefor;

Fig. 6e is an enlarged detail view of the supporting box and upper edge of the front panel structure;

Fig. 7 is an enlarged detail, horizontal sectional view of the rear end wall, the sectional plane being taken on the line 7 7 of Fig. 1;

Fig. 8 is a vertical Sectional View taken on the line 8 8 of Fig. 7;

Fig. 9 is a further enlarged, horizontal sectional view of the spring-supported anchor for the upper header of the huid-cooled structure, the sectional plane being taken on the line 9 9 of Fig. 1;

Fig. 10 is a vertical sectional View taken on the 11n@ 10-10 of Fig. 1; 90

Fig. 10c is a side elevational view of the structure ofk Fig. 10;

Fig 10b is an enlarged detail View of the interconnected anchoring means for the expansible rear panel structure;

Fig. 10c is a similar view but showing the portion of the rear wall through which the upper ends of the cooling pipes extend;

Fig. l1 iS a view similar to Fig. l, but show- 100 an alternative embodiment of my invention;

Fig. 12 is an enlarged horizontal Sectional view taken onv the line 12-12 of Fig. 11;

Fig. 13 is a further enlarged, horizontal sectional view of the lower corner portion of the front protective panel, opposite to that shown in Fig. 12;

Figs. 14 and 15 are sectional views taken on the lines 14 14 and 15-15, respectively, of Fig. 13;

Fig. 16 is an enlarged detail View of the cush- 110 ion support for the upper header of the protective structure;

Fig. 17 is an enlarged front elevational View of the structure of Fig. 11, certain of the parts, however, being omitted;

Fig. 18 is a rear elevational View of the structure of Fig. 11 with certain of the parts omitted as in Fig. 17;

Fig. 19 is an enlarged detail, transverse sectional View through Vthe rear end wall of the furnace shown in Fig. 11, the sectional plane being tal-ren on the line 19-19 thereof;

Fig. 20 is an enlarged, detail, vertical sectional view of the end wall and adjacent side-wall portion of Fig. 11, the sectional plane being taken on the line 2O 20 thereof;

Fie. 21 is a view similar to Fig. 20, the section, however, being taken on the line 21-21 of Fig. 11; and

Fig. 21a is an enlarged detail view of the lower portion of the rear panel of Fig. '11 as the supporting means therefor.

Referring to Figs. 1 to 10, inclusive, an inclined multiple retort automatic stolrer 1 of the underfeed type extends rearwardly from a furnace opening 2 in a front end Wall 3, to a main supporting 1oeam 4. A rear portion 5 of the stoler 1 is spaced from a rear end wall 6 of the furnace to provide an ash pocket 7.

The stolzer structure 1 comprises in part a plurality of series of inclined tuyres 8 and a corresponding plurality of series of retorts Salternating therewith, only one series of each, however, being shown. A sufficient number of series of tuyres 8 and retorts 9 is provided to extend across the Width of the furnace into proximity with furnace side Walls 11, of which one only is shown. n

A fuel bed may be built up on the grate surface provided by the inclined stoker 1, as indicated in dot-and-dash lines in Fig. l, and slowly moved by means of a series of pushers 12 which are actuated by mechanism 13, forming no part of the present invention. The retorts 9 in which the pushers 12 are contained may receive fuel from a hopper 14 through the stoker openings 2 in the front wall 3.

The portion of each of the furnace side Walls 11, which is directly subjected to wear and deterioration due to the movement of the fuel bed may be protected by means of a fluidcooled panel structure or curtain 15, the width of which is at least suiicient to prevent the fuel bed from coming into direct contact with a brickwork portion 16 Vof the furnace side walls,

and the inclination of which is approximately equal to that of the Stoker 1 or the tuyre line thereof. It is noted that certain features of the protective-panel structure 15 associated with leach of the side walls 11 are disclosed and -is below the heated portion of the fuel bed.

The width of the opening 17 is rsuch that anV upper edge or side Wall 13 is just above the top of the fuel bed. The opening 17 maybe eX- tended across the side wall from a front Wall 3 to the rear wall 6.

Briefly, the fluid-cooled panel structure 15 comprises a plurality of inclined pipes or tubes 21 which extend from an upper front header 22 positioned on the outside of the furnace to a lower rear header 23 also exteriorly positioned. These inclined pipes are positioned in spaced relation and in a common vertical plane between an inner side 24 of the side Wall 11 and an outer side 25 thereof. Protection is afforded the pipes 21 against the direct heat of the furnace by means of a plurality of refractory blocks 26 which are positioned in side-by-side and superposed relation, forming, respectively, a plurality of vertical and inclined rows.

An inner side of the blocks 26 is recessed so as to embrace at least partially the circumference of an adjacent cooling pipe 21 and it is releasably secured in this position by means of bolts 27 and vertical angle members 28. An inner side 29 of the panel structure 15 is maintained in alignment with an adjacent inner side 31 of the brickwork portion 16 of the side wall 11 by means of an open framework 32 and a bearing pin structure 33, as shown in Figs. 2 and 7. The open framework 32 permits access therethrough to the panel structure 15 from the outer side 25 of the side Wall 11, without the necessity for removing any of the brickwork. The bearing pin structure 33 permits the panel 15 to expand relatively to the open framework 32. Inasmuch as the detail structure of the parts 32 and 33 is set forth in detail in the above-noted co-pending application of Edward Wheeler, a further description is deemed unnecessary.

Referring to the front wall 3, which constitutes one of the important parts of my present invention, as shown in Fig. 1, this wall comprises an upper briclrwork portion 35,' a fluidcooled protective-panel structure 36 and a ramcap structure 37. The fluid-cooled protective structure 36 comprises a pair of upper and lower headers 38 and 39 which are interconnected by a plurality of upwardly extending pipes 40. Each of the pipes 40 comprises a vertical portion 41, which is'connected at its lower end to the header 39, and a forwardly extended portion 42 which terminates in the upper header 33. The length ofthe vertical portion 41 of the pipes is usually dependent upon the height of the boiler setting.

The pipes 40 are protected against the direct heat of the furnace by means of a plurality of refractory blocks 43 (Figs. 1 and 2) which are positioned in side-by-side and superposed relation so as to form a plurality of vertical and horizontal rows. en inner side of each of the blocks 43 is provided with a vertical recess 44 adapted to receive at least a portion of one of the vertical pipe portions, and it may be, clamped in this position by means of a pair of bolts'45 and 46, which extend from a vertical flange 47 of a horizontally positioned angle section 48 to threaded borings 49 and 51 formed in the inner side of the protective block 43. 1n this manner, the angle member 43, the block 47 and the pipe 21 are rigidly secured together.

Instead of a single angle member 48 extending continuously across the entire width of the furnace, may employ a plurality of short sections, one for each of the blocks 47. Such construction has the advantage that should it be desirable to replace only one of the blocks 43 in horizontal row, it is not necessary to remove an angle member which extends the full width of the stoker, but only a section of approximately the width of one of the blocks 43. `The sectional angle members 38 associated with the vertical portion 41 of the tubes are replaced at the curved portion 42 by means of a bar 53 which is bolted to a modified form of refractory block 54. A further modiied refractory block 55 is mounted immediately above the block 54 so as to protect further the curved portion 42 of the tubes from the furnace heat. A plurality of tiles 56 extend vertically from the refractory blocks 55 to the brickwork portion 35 of the front wall 3.

In accordance with my invention, the protective panel structure 36 is mounted independently of the stoker 1 and, more especially, the rambox cap portion 37 thereof,-my invention further contemplating the suspension of the structure 35 from a point preferably above the stoker 1 and the provision of means 57 (Figs. 1, 2 and 3), whereby the structure 36 may be maintained in position while permitting expansion to occur. To this end, I mount the upper header 38 in openings formed in the spaced side wall portions 58 and 59 of a plurality of cast iron supporting boxes 61. The boxes 61 are positioned in side-by-side relation across the width of the front wall 3 and are mounted on a pair of cross -beams 62. The ends of these beams are supported independently of the Stoker 1, preferably in the side walls 11 and if necessary on side wall boiler columns 63. Thus, the wail structure 36 is afforded a suspended mounting independently of the Stoker structure.

The cast iron boxes 61, of which Fig. 1 shows a vertical, sectional View and Fig. 6 an end elevational View, comprise a bottom wall 64, which ismounted on the cross-beam 62, an upper wall 65 for supporting the brickwork portion 35 of the front wall 3 and the apertured spaced walls 58Y and 59. A rear side 66 is closed by the tile portion 56, while a front side 67 is open, so that access may be had from the exterior to a manhole 68 disposed in that portion of the header between the side walls 58 and 59. The lower side 64 is provided with a centrally disposed raised portion 69 having an angularly disposed side 71 affording a supporting shoulder for the portion of the pipe immediately adjacent to the header 38.

In practice, it is an exceedingly simple matter to install the protective structure 36 to existing installations, since there is no interference with the coal feeding or driving mechanism and the weight of the structure 36 is not supported on the stoker but instead on the side walls 11. The only structure that must be addedY to the main supporting steel work is the cross-beams 62. When the structure 86 is being installed7 the beams 62 are first mcunted in the side` walls 11, and the cast iron boxes 61 are next positioned on the crOss-beams-SZ. Then, the header 38 is passed through the boxes 61 and so positioned that manholes 68l thereof are disposed in the open space of the `boxes 61 facing theV exterior. Hence, access may be had to the interior of the furnace header 38 from the outside of the furnace, so that the upper ends of the pipes 49 may be expanded in the header 38. It is noted that the above installation work may be done in the field.

Another feature of the front wall 3 is the means 57 which serves to tie-in the lower free edge portion of the panel structure 36, while permitting expansion to occur. As shown in Figs. l,

2 and 3, a lower angle section 72, which co-operates with a refractory block 73 in the bottom row immediately adjacent to one of the side walls l1, is provided with a pair of clamping or tie' bolts 74 and 75 having extended portions 76 and 77. The portions 76 and 77 are secured by nuts 78 and 79 to the web portion 81 of a vertical channel member 82. y Thelower end of the channel member 82 is secured by means of a bracket 83 lto a front plate section 84 of the stoker structure, while an upper end is similarly secured to the cross-beams 62. A similar tierod construction (not shown) is provided for the lower corner portion of the panel 36 immediately adjacent to the side wall 11 opposite to that just-mentioned. The length of the extension portions 76 and 77 of the pair of ,tierods 74 and 75 is sufficient to permit the same to flex and the structure 36 vto expand or contract. It is thus apparent that the lower free edge portion of the panel structure 36 is 'prevented from swinging inwardly or outwardly of the furnace about the suspension support afforded by the cross-beam 62 and the supporting boxes 61, while, at the same time, expansion is permitted to occur, soY that the danger of a disalignment of Vthe panel structure 36 due to a bulging of the same is eliminated. l

A still further feature of the furnace front wall 3 is the structure 37 which embodies means for preventing an upward movement of ram-box caps 85 when coal is being forced therethrough. This is necessary inasmuch as the weight of the wall portions 35 and 36 is not carried by the structure 37, but rather by the cross-beam 62 extending between the furnace side walls l1.` Referring to Figs. 1, 3, 4 and 5 in detail, the structure 37 is provided with the plurality of supporting boxes 86 which are mounted on a portion 87 of the stoker structure. The pluralty of ram-box caps 85 are positioned intermediate the boxes 86, forming the furnace openings 2 through which the fuel passes. Vertical movement of the ram-box caps 85 is prevented by reason of blocks 88 which are positioned between the upper side of the ram-box caps 85 and an underside of a cross channel 89 extending between the furnace side walls 11 and mounted on an upper side of the boxes 86.

The cross channel member 89 may be secured in position in any one of a number of ways.

VFor example, each of the boxes 86 and the adjacent portion of the supporting structure 87 `may be provided with apertures 91 and 92 through which a hook bolt 93 extends. A lower lcurved portion 94 of the hook bolt 93 extends around and engages a shoulder portion 95 of the stoker structure immediately below the supporting structure 87. An upper threaded end 96 of `the bolt 93 extends through the cross channel89 and a nut 97`engages the same and an upper side 98 of the channel 89 securely locking the bolt 93 in position. It is noted that the cross channel 89, the cap spacer blocks 88 and the hook bolts 93 are the only special parts that must be added to the stoker l and that these parts may be very easily mounted on a stoker of any standard design.

In order to permit relative movement between the lower header 39 and the ram-box structure 37, a small space is provided which may be filled with an elastic packing 99. The passage of heat through 'the structure 36 may be further prevented by coating the inner side of the refractory blocks with a plastic cement 101, say one-half inch thick. In addition, a second layer of cement 102 is provided which extends between the' coating 101 and the outer edge of the clamping channel sections 43. Maximum protection is assured by covering the outer side of the layer 102 with a iinishing coating oi hard cement of about one-half inch thickness. Y

Referring to the illustrated embodiment of my invention shown in Figs. 1 and 7 to l0, inclusive, the rear end wall 6 oi the furnace comprises at least three main portions or sections, viz., a duid-cooled protective panel structure 103, which is supported directly on a plurality of spaced brackets 104 constituting one part of the stolzer structure; a brick and tile portion 105, which is mounted on a pair of cross-beams 106 supported in the furnace side walls and, more especially, on vertical side-wall columns 107, so that a support may be aiorded the brickworlrportion 105 independent of the stoker structure; and a tile o1` brickwork portion 10S, which is provided with an expansion joint 100, permitting an upward movement of the protective panel structure 103 when expansion occurs. A cushion-supported anchor 111 is connected to an extended portion 112 of the protective panel 103, and it serves to maintain the proper alignment of the panel structure 103 when expansion occurs.

ConsideringT more specifically the protective panel structure 103, a plurality of substantially vertical pipes 113 are provided with lower, rearwardly curved end portions 114 which terminate in a lower header 115 which is supported by the spaced brackets 104. 1n this manner, substantially the entire weight of the Apanel structure 103. is carried by the stoker structure. Protection is afforded the pipes 113 by means of a plurality of refractory blocks 116 which are positioned in side-by-side as well as superposed relation, forming respectively a plurality of' vertical and horizontal rows.v Each block is recessed so as to receive at least a portion of an adjacent pipe, and it may be releasably secured in this position by means of a pair of bolts 117 which extend from a vertical flange portion 118 or" a horizontally positioned angle 119. The angles 119 which are associated with each horizontal row together' form an elongated sectional 'angle member 121, there being one such meniber 121 for each horizontal row. While the member 121 may be integral throughout its.

length, it is vpreferable to divide the same into sections, so that should only one of the refrac-l tory blocks in any horizontal row be damaged, it would not be necessary to remove the whole angle member 121 but only one section thereof.

As shown in Figs. 7 and 8, a packing 122 is inserted between the side-wall panel structure 15 and the vvertical row of refractory blocks irnmediately adjacent thereto. The packing 122 is prevented from being displaced upon the occurrence of lengthwise expansion of the furnace between the supporting brackets 104 maybe Vclosed by means of a plurality of plates 128, which; extend between successive supporting brackets. The plates 128 vare also protected by the insulating layers 125, 126 and 127.

The wall portion 105 comprises a rear brickwork portion 129 and a front tile portion 131. These portions bear directly against a plate 132 supported on the side-wall supported crossbeams 106. The tile portion 131 comprises a plurality of vertically disposed tile members 133, each of which is positioned in a recess 134 in the brickwork portion 129. Each recess comprises a verticle side 135 and a horizontal side 136. The tile 133 is provided with complementary horizontal and vertical sides 137 and 138. The horizontal side 137 of the tile 133 extends beyond the side 136 of the recess 134 to provide a supporting shoulder portion for an upper tile 139. The tile 139 is'similar to the tile just described and it similarly supports a third tile 141.

' Each of the tiles is provided with an inclined front face 142 over which extends the vertical pipes from the panel structure 103. Upper end portions 143 of the pipe extensions are curved,

f as shown in Fig. 1, extending into a horizontal portion 144 terminating in an upper exteriorly positioned header 145. An upper edge 146 of the brickwork portion 105 is curved complementary to the curved portion 143 of the pipe extension, and it is separated therefrom by means of an elastic packing `147.

The portion 10S of the rear end wall 6 comprises an upper rigid wall portion 148, a lower relatively movable portion 149 and the expansion joint 109. The lower portion 140 comprises tile members 151 and 152, the tile member 151 being clamped to the curved portion 143 of the pipe extensions by means of a bolt 153 and a clamping bar 154. The tile portion 152 also rests on the curved pipe portions 143, as well as the tile 151. The tile 152 has a right-angle portion 155 which slidably engages a complementary portion 156 of a tile 157 constituting one part of the upper rigid wall portion 148. In this manner, the expansion joint 109 in the third portion 108 of the rear end wall 6 is formed. Each of the tiles 157 is interlocked with a bracket 158 supported on a cross channel 159 carried by the side walls 11.

One of the important features of my invention is the provision of simple and efficient means whereby the panel structure 103 may expand and contract without causing the buclfling of any portion thereof. To this end, I provide the cushion-supported anchor 111 which is illustrated in Figs. 1, 9, and 10. As therein disclosed, a divided collar 161, comprising parts 162 and 163, is clamped on the upper header .145Y by means of horizontally positioned bolts 1764. The parts 162 and 163 are respectively 'provided with apertured shoulders 165 and 166 through which extend vertically positioned bolts 167 and 16S.

llO

as Well as the adjacent end portion of the pipe extensions. i i Vertical ilanges 177 of the upper and lower angles 171 and 174 are secured -to a flange portion 178 of a vertical I-beam 179, as shownin Fig. 9. An opposite flange 181 is secured to a web portion 182 of a second I-beain 183 which is positioned at right angles to the I-beam 179. The I-beam 183 is preferably positioned. in or immediately adjacent to the side walls 11, and it may serve further to support the crossbeams 106 which are associated with the brick- Work portion 105. Each end of the upper header 145 is resiliently supported by the anchor means 111 just described, and intermediate supports of a similar character may be provided if necessary.

When the expansion occurs, the upward move ment of the pipes 113 causes the movable wall portion 149 of the third Vwall section 108 to move relative to the adjacent stationary porn tion 148, by reason of the presence of the eX pension joint 109. During such movement, the alignment of the panel structure 103, as well as the pipe extensions 112 thereof, is maintained by reason of the'cushion anchors 111 associated with the upper'header 145; Any possible tendency for buckling to occur may be further prevented in the manner shown in Fig. 10b, wherein a'iiange 184 of an angle 185, which is horizontally, disposed adjacent to the upper edge of the panel structure 193 and secured thereto by means of clamping bolts is provided with a plurality of apertures 186 for end portions 187 of a plurality of bolts 188 mounted in an inner iiange portion 189 of one of the cross supporting beams 106.l Y

Referring to the alternative embodiment of my invention shown in Figs. 11 to 18, inclusive, a front end wall 191 comprises an intermediate protective panel portion 192, a lower portion 193 and an upper brickworli portion 194 over which pipe extensions 195 from the panel structure 192 extend. The protectivepanel structure 192 comprises a plurality of vertically positioned pipes 196, lower endsv of which are secured to a header 197, which is supported directly on the portion 193 of the front wall 191, rather than independently thereof, as in the front wall 3 of Fig. 1. The lower portion 193 comprises a lower bricljiworl: portion 198 and a supporting rambox cap structure 199, the latter being carried by the stoker structure l. Thus, substantially the full weight of the panel structure 192 is carried by the Stoker structure. V

The detail construction of the fluid-cooled panel 192 is substantially the same as that of the panel structure 136 shown in Fig. 1, comprising a plurality of refractory blocks 200, a

plurality of horizontally positioned angle mem-V bers 201 and a plurality of clamping bolts 202.v

The insulation of the panel structure 192 andV the ram-box cap structure 199 may be increased by means of a plurality of insulating layers 203, 204 and 205 of refractory material, `as shown in Figs. 11 and 12.

The upper brickwork portion 194 or" the front wall 191 is supported on the stolzer structure open chamber portion 208 of the front wall 191 immediatelyin front of the panel 192. Lower with the upper headerv 217 which permit the verends of the columns 206 are supported on a horizontal flange 209 of a front plate portion 211 of the stoker structure. Hence, theupper brickworl; portion 194 is directly supported on the stoker structure, rather than on a pair of cross-beams extending between the furnace Vside walls 11, as in the front end wall 3 of Fig. 1. Y

The lower header 197 ofthe panel structure 192 may be further rigidly secured in position in the manner shown in Figs. l1 to 15, inclusive, wherein a tie-rod 212 extends forwardly from a front side of the header 197 to a bracket member 213, in which it is securely bolted. The bracket 213 is also carried on the horizontal flange 'portion 209 of the front stoker plate 211. While only one tie-rod is shown, it is understood that a sufficient number are to be used, so that the lower edge portion of the panel structure 192 may be maintained in position when eX- pansion occurs.

As shown'in Fig. 11, the extended portions 195 of the cooling pipes comprises vertical portions 214,v curved portions 215 and horizontal portions 216 which terminate in an exteriorly positioned upper header 217. The header 217 is afforded a cushion support by means of a plurality of spring anchor devices 218, as illustrated in Figs. 11, 16 and 17. Each of these anchors comprisesY a bracket 219, which is secured to the header 217 by means of a U bolt 221, and a pair of downwardly extending spaced pins or rods 222 and 223. The pins 222 and 223 extend through upper and lower ilanges 224 and 225 of a pair of channel members 226 and 227, respecn tively. Cushion springs 228 and 229 abut against the lower flanges 225 andnuts 231, which are rigidly secured to the rods 222 and 223. Hence, the weight of the header 217 is carried by the cushion springs 228 and 229. As shown in Fig. 17, the channels 226 and 227 are supported on exteriorly positioned vertical I-beams 232.

When the panel structure 192 expands upwardly, movement of the lower header `197 is prevented by reason of the tie-rods 212 as well as the fact that the entire weight of the structure iscarried by the lower portion 193 of the front wall 191, which directly engages the header 197. When the'pipes 192 as well as the extension porm tions 195 thereof move upwardly, the curved and horizontal portions 215 and 216 move away from a complementary curved edge portion 233 of the upper briclrwork portion 194 oi' the front wall 191. l'isalignment, however, is prevented by reason of the cushion anchors218 associated tical movement just-mentioned but prevent a horizontal movement. Thus, a bulging of the pipes is prevented andthe proper alignment oi the protective structure 192 is assured.

rThe rear end wall234 shown in Figs. 11, 19, 20 and 21 comprises a protective panel structure 235 and a brickwork portion 236. The protective panel structure 235 comprises a plurality of pipes 237 whichk extend upwardly from a lower header 238 mounted on a plurality of brackets 239 extending from a cross supporting beam 241 of the stolzer structure. The lower header 238 may be rigidly clamped to the brackets 239 by means of a plurality of bolts 242 which extend between an angle 243 mounted on an upper side of the header 239 and thebrackets 239.

The protectivev panel structureV 235 further comprises a plurality of refractory blocks 244,

a plurality of sectional angle members 245 and 150 a plurality of clamping bolts 246, as in thecase of the front-wall panel structure 36 of Fig. 1. As shown in Fig. 1l, the pipes 237 comprise a vertical portion 247, a curved portion 248 and a horizontal portion 249, the latter portion extending rearwardly and outwardly from the furnace to an exteriorly positioned upper header 251.

The clamping angles 245, which are associated with the vertical portion 247 of the pipes, are replaced in the curved portion 243 by means of a plurality of bars, as shown in Fig. 21. The refractory blocks 244, which are immediately adjacent to a side-wall panel structure 253, are separated therefrom by means of packing 254. In order to prevent the packing 254 from being displaced, when the 'protective structure 253 expands relative to the end wall 235, I provide aplurality of plates 255, edges 256 of which abut against the side-wall panel structure 253. The plates 255 are secured in position on adjacent angle sections 245 by the clamping bolts 246. As shown'in Fig. 21, the plates 255 may be replaced by a single strip member 257 in the curved portion of the panel structure 235.

The upper brickwork portion 236 of the rear end Wallis supported on a pair' of cross I-beams elongated castiron box 261 having upper and lower wallsv 262 and 263 and intermediate walls 264, forming a plurality of chambers 265 through which extend the horizontal portions 249 of the pipes. An elastic packing material 266 is inserted in these chambers, so that the end wall per header 251.

tical in all respects to that associated with theV and a pair of supporting springs 273.

'the panel structure 235 occurs.

235 may be further sealed at this point, all as illustrated in Figs. 11 and 19.

A further feature of the rear end wall 235 is the cushion supporting means V267 for the up- This supporting means is identhe cushion supporting means 267'for the upper header 251, this upward movement occurs without a resulting buckling or disalignment of the Aprotective panel structure 235. Y

`While I have shown several. embodiments of my invention, for the purpose of describing the same and illustrating its principles of construction and operation,` it is apparent that various changes and modications may be made therein, without departing from the spirit of my in- By reason of vention and IV desire, therefore, that only such limitations shall be imposed thereon as are indicated vin the appended claims or as are demanded by the prior art. f

I claim: Y

l. In a furnace, a wall structure comprising a huid-cooled freely depending panel, said panel comprising a plurality of pipes, a header connected with the upper ends of said pipes and from which said pipes depend, liner elements secured to and supported by said pipes and forming the effective wall surface, and flexible members attached to a linerelement in the lower part of said panel and to a relatively fixed structure and constituting means for preventing undesirable displacements of the lower free end of the panel while permitting expansion and con- 'raction inthe panel as a Whole due to temperoverlying and in substantial vertical alignment with said ram boxes, said Wall structure comprising a lower freelyl depending section terminating lat a point adjacent the tops of said boxes, iiexible packing'means closing the joint between the tops of said boxe-sand the lower edge of said depending wall section, and means independent of said wall section for maintaining the tops of said boxes in position.

3. 'In afurnace, the combination with a stoker comprising a grate and a plurality of ram boxes through which fuel is fed to said grate, each of said boxes having a detachable top member, a furnace front wall in substantial vertical alignment withrsaid boxes but supported independently thereof, a transversely extending beam supported in a position overlying said ram boxes, and elements cooperatively associated with said beam and said rain box top members to retain the latter in position.

4.v In a furnace, a wall structure comprising a fluid cooled freely depending panel, said panel comprising a plurality of pipes, a header connected with the upper ends of said pipes, and from which said pipes depend, liner elements secured to and supported by said pipes and forming the eifective wall surface, and flexible memers attached to said panel and to a relatively fixed structure, and constituting means for preventing undesirable displacements of the free end of the panel while permitting expansion and contraction ,in the panel as a whole due to tem- Aperature changes 'affecting the panel, said ilexible members comprising one or more rods, and

Vmeans for securing one-end of said rods to said xed support and the other end thereof to said panel.

JOSEPH S. BENNETT. 

